Strophiops lineota Maynard, 1889

Original Description

"7. STROPHIA LINEOTA Novo.

Lined Strophia.

Plate II, 7 & 7B, shell.

DESCRIPTION.

            SP. CH.  The size is medium. The shell is rather heavy. The striations are present. Tentacles, about one third as long as the eye peduncles, Teeth, two and quite long. Whirls, 10. Examined 1,000 specimens.

            Form of shell, cylindrical, with the first three whirls equal in diameter. From the third whirl, the shell slopes rapidly to a point, making an angle of 65 degrees. The striations are rather numerous, 20 on the upper whirl, prominent, regular, although not arranged in lines; they are slightly inclined from right to left, and the interspaces are about equal in width to the prominences. The striations are not furrowed and the edges are smooth and rounded.

            Aperture, large and open, measuring a trifle more just within than at the entrance. Lower tooth, not very prominent, .04 high by.18 long, and its position is about its width to the right of the center; the upper is not as prominent, is placed considerably above it, .05, and measures .02, but makes a complete turn around the column.

            Margin, not produced forward beyond the diameter of the shell, but is inclined slightly to the right, beyond the side; it is not greatly thickened, measuring .04, but the outer posterior portion is produced backward into a thin, but not prominent, edge that is rolled slightly downward. The frontal bar is not well developed, and the striations appear within it, but beneath the translucent enamelling [sic] of the lower wall, and are thus not elevated. The animal is not very large; eye pe­duncles, .12 long; tentacles, .04.

            Color of shell externally, white, with most of the interspaces betweem the striations, dull purplish brown; internally, of rather a pale purplish brown which becomes paler on the lower wall of the aperture, and fades on the upper walls and teeth, into yellowish white. Color of animal, very dark brown, with the bottom of foot, eye peduncles, tentacles, and top of head in front of tentacles, horn color.

DIMENSIONS.

            Size of types, 1.04 by .40 and .98 by .42. Largest specimen, 1.10 by .46; smallest, .74 by.36. Greatest diameter, .46; smallest, .36. Longest :specimen, 1.10; shortest, .74.

OBSERVATIONS.

            Individual variation is not great, the type form being very constant.

            Two forms occur besides, one of about the same form, but with the aperture inclined well to the right, and the shell is larger, thicker, and whiter, with fewer markings; while the other is shorter and proportionally a little thicker, with the markings in some instances, extending across the striations. The margin is never heavy, .08 being the extreme meas­urement. Striations vary from 18 to 20.

            Known from S. copia, its nearest ally, by the prominent markings, and from all others, by these and the long teeth.

DISTRIBUTION AND HABITS.

            I found the Lined Strophia in a small cocoa-nut grove on the south side of Little Cayman, near the east end, and more rarely in the cocoa-nut grove near the boat landing, on the south side of Cayman Brac. This spot on Little Cayman, about a half acre, was occupied by them exclusively, while on the other key, they mingled with the Common Strophias. They were probably transported from one place to the other by boat, the original locality, probably, being Little Cayman.

            The cocoa-nut grove where I found these Strophias, was situated directly on the shore, some miles from any settlement, and was com­pletely isolated from all other colonies of Strophias. The width of the key intervened between this point and a colony of S. copia on the north shore, two miles, at least, of nearly naked, jagged rocks, as impassable to a mollusk of this species, as would be the wide Atlantic, and there was no vegetation in this direction, to induce them to extend their colony, and between them and the several species that occupied the west end of the island were miles of rocky country and the mangrove swamp.  I found them very abundant, clinging to the fallen cocoa-nut leaves and other debris that lay upon the ground. They were gathered in close clusters of many individuals, often one top of another." (Maynard, 1889:20-22)

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